Right now, you can hop onto PlayStation Now to play through Red Dead Redemption and its stellar, zombie-themed Undead Nightmare expansion. In case you need some sort of a refresher on Red Dead Redemption, read on.
Red Dead Redemption
Starting today, re-live the epic story of former outlaw John Marston all over again in Red Dead Redemption.

America, 1911. The Wild West is dying. When federal agents threaten his family, former outlaw John Marston is forced to pick up his guns again and hunt down the gang of criminals he once called friends. Experience an epic fight for survival across the sprawling expanses of the American West and Mexico, as John Marston struggles to bury his blood-stained past, one man at a time.

Red Dead Redemption: Undead Nightmare
You can also return to the Undead Nightmare, where an undead plague is spreading across the frontier.

When former outlaw John Marston wakes up at his farmhouse, he finds a world gone insane: overnight, deranged hordes have overrun the towns and outposts of the American frontier. In a desperate attempt to save his family, Marston must traverse a world torn apart by chaos and disorder, using every skill he has to survive long enough to find a cure.

Sony also announced today that they're bringing back the year-long subscription to PS Now for $99.99 (USD). This will be available for only a limited time. If you want to try before you pay, there is a free seven day trial to PS Now.